Small power wind systems automatic control

Abstract

Given the increasing interest in small wind systems, the authors propose three applicable control strategies, confirmed by Matlab/ SimPowerSystem simulation software in terms of energy conversion optimization and stable operation. The analyzed small power wind energy conversion system has a Permanent Magnet Synchronous Generator — PMSG, a diode rectifier, a DC-DC converter, a battery and DC consumers. In order to highlight the performances of the small power wind system three control solutions were investigated in order to obtain maximum power conversion and stable operation. For the first case a shaft rotational speed loop with reference depending on the wind speed was used and for the second, a power loop with reference depending on shaft rotational speed cube and reaction after the electrical power. The third case had a power loop and a shaft rotational speed loop. In all the cases the chopper that feeds the battery uses an on-off controller.